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Optimal power flow with generation reallocation is a suitable method for better utilization of the existing system. In recent years, Flexible AC Transmission System (FACTS) devices, have led to the development of controllers that provide controllability and flexibility for power transmission. Out of the FACTS devices unified power flow controller (UPFC) is a versatile device, capable of controlling the power system parameters like voltage magnitude, phase angle and line impedance individually or simultaneously. The main aim of this paper is to minimize real power losses in a power system using BAT search algorithm without and with the presence of UPFC. Minimization of real power losses is done by considering the power generated by generator buses, voltage magnitudes at generator buses and reactive power injection from reactive power compensators. The proposed BAT algorithm based Optimal Power Flow (OPF) has been tested on a 5 bus test system and modified IEEE 30 bus system without and with UPFC. The results of the system with and without UPFC are compared in terms of active power losses in the transmission line using BAT algorithm. The obtained results are also compared with Genetic algorithm (GA). [ABSTRACT FROM AUTHOR]

Abstract: Radicamine B 5 was synthesized from p-hydroxy benzaldehyde 7 stereoselectively using acid catalysed amido cyclisation with the help of neighbouring group participation (NGP). Without NGP both radicamine B 5 and its epimer 5-epi radicamine B 6 were obtained. The key steps of the synthesis are Sharpless asymmetric dihydroxylations and acid mediated amido cyclisation. [Copyright &y& Elsevier]

Abstract: The highly stereoselective Grignard addition on chiralimine 8 and opening of chiral epoxide 9 with Grignard reagent have been used as key steps in the stereoselective synthesis of cytotoxic anhydrophytosphingosine pachastrissamine (jaspine B) and N,O,O,O-tetra-acetyl d-lyxo-phytosphingosine. [Copyright &y& Elsevier]

Abstract: A common and stereoselective strategy for the synthesis of N,O,O,O-tetra-acetyl d-ribo-(2S,3S,4R)-phytosphingosine and 2-epi-jaspine B was achieved by using Grignard addition on N-benzyl sugar lactamine and Wittig olefination as key steps. [Copyright &y& Elsevier]

Abstract: A new stereoselective approach for the synthesis of N-benzyl amino(hydroxymethyl)cyclopentitols by using stereoselective allylation on lactamine and RCM from d-ribose has been described and the glycosidase inhibitory activities of these amino cyclopentitols have been studied. [Copyright &y& Elsevier]

Abstract: Nd3+ doped fluorine containing zinc-aluminophosphate glasses have been prepared with alkali and alkaline earth content to understand the effect of network modifiers on radiative process. The physical and optical properties of these glasses have been evaluated. The Judd–Ofelt model for the intensity analysis of induced electric dipole transitions has been applied to the measured oscillator strengths of the absorption bands to determine the three phenomenological intensity parameters Ω 2, Ω 4 and Ω 6 for each glass. Using these parameters, transition probability (A), total transition probability (A T), branching ratios (β R) radiative life times (τ R) and integrated cross-section (σ a) for the stimulated emission have been theoretically calculated for certain excited Nd3+ fluorescent levels. From the obtained results the conclusion is made about the possibility of using these glasses as laser material. [Copyright &y& Elsevier]

Abstract: A short synthesis of hydroxyethylene dipeptide isostere, a core unit of the HIV-protease inhibitors ritonavir and lopinavir, its C-3 epimer and C 2 symmetric diamino diol is described. The crucial aspects of the synthesis are self-cross metathesis and exploitation of C 2-symmetric of the metathesis product 8 to obtain the required skeleton. [Copyright &y& Elsevier]

Abstract: An efficient and highly stereoselective approach to bicyclic aza sugars is described using Grignard reaction on an N-benzyl imine derived from 3-O-benzyl-1,2-O-isopropylidine-α-d-xylo-pentodialdofuranose, ring closing metathesis, and reductive cyclization as key steps. [Copyright &y& Elsevier]

Abstract: A novel stereoselective synthesis of N-Boc-(2S,3S)-3-hydroxy-2-phenylpiperidine was achieved from d-mannitol involving the highly stereoselective addition of phenyl Grignard to an allyl imine (de >98%) and ring-closing metathesis (RCM) in the key steps. [Copyright &y& Elsevier]

Abstract: A Chiron approach for the synthesis of (+)-secosyrin 1 from d-mannitol has been described. The key steps are a stereoselective Wittig reaction and an intramolecular Michael addition on the disubstituted butenolide, leading to a highly stereoselective formation of the tertiary chiral centre of (+)-secosyrin 1. [Copyright &y& Elsevier]

A series of trivalent gadolinium (Gd3+) doped lanthanum phosphates (LaPO 4) were prepared by the co-precipitation technique with varying concentrations of Gd3+. The structural properties of the prepared phosphor samples were analyzed by X-ray diffraction (XRD) which showed monoclinic structure of LaPO 4. The photoluminescence (PL) emission spectra of the Gd3+-doped phosphor excited at 272 nm consists of dominant UVB emissions at 312 nm corresponding to the P 7 / 2 → 8 S 7 / 2 6 transitions of Gd3+. The electron spin resonance (ESR) spectra of LaPO 4 :Gd3+ phosphor reveal three significant attributes with effective g-values around 6, 2.8, 2.0 and a feeble characteristic at 4.8 owing primarily to the presence of Gd3+ ions in clustered species. [ABSTRACT FROM AUTHOR]

Abstract: The stereoselective synthesis of 6-epi-pentenocin B 3 is described using a stereoselective Grignard reaction and ring-closing metathesis (RCM) as the key steps. [Copyright &y& Elsevier]

Asymmetric syntheses of (1R,1′R,5′R,7′R) and (1S,1′R,5′R,7′R)-1-hydroxy-exo-brevicomins 1 and 2, volatiles of the male mountain pine beetle, and a formal synthesis of (+)-exo-brevicomin 3, a component of the attracting pheromone system of several bark beetles have been achieved. The key steps are Birch reduction of commercially available α-picoline, selective Wittig olefination, and Sharpless asymmetric dihydroxylation. [Copyright &y& Elsevier]

A stereoselective synthesis of 1,4-dideoxy-1,4-imino-d-allitol 1 and formal synthesis of (2S,3R,4S)-3,4-dihydroxyproline was achieved via the addition of vinylmagnesium bromide to the benzylimine derived from (R)-2,3-O-isopropylidene glyceraldehyde followed by N-allylation, ring-closing metathesis (RCM), and dihydroxylation. [Copyright &y& Elsevier]

An efficient and stereoselective synthesis of protected (2R,3R,4S)-4,7-diamino-2,3-dihydroxyheptanoic acid, a constituent of the depsipeptides, callipeltins A and D, from d-ribose is described. [Copyright &y& Elsevier]

An efficient synthesis of enantiopure (−)- and (+)-pentenomycins are described by reductive iodo elimination and ring-closing metathesis (RCM), as the key steps. The first synthesis of the unnatural (+)-isomer is described. [Copyright &y& Elsevier]

Enantioselective synthesis of non-peptidic neurokinin NK1 receptor antagonist L-733,060 is described using ring-closing metathesis as a key step, starting from l-phenylglycine. [Copyright &y& Elsevier]

Abstract: A common method for the synthesis of 4a-carba-β-l-lyxofuranose and 4a-carba-β-l-arabinofuranose from d-mannose and 2,2,5-trimethyl-3a,6a-dihydro-cyclopenta[1,3]dioxol-4-one from d-ribose is described using catalytic Nozaki-Hiyama-Kishi (NHK) conditions and ring closing metathesis (RCM). In this transformation, ω-deoxy-ω-iodo manno/ribo furanoside undergoes reductive elimination in the presence of Mn/CrCl3 to give the corresponding olefin-aldehyde which was trapped by nucleophile under the same conditions to afford the desired diolefinic species. The ring closing metathesis reaction on these diolefinic species with Grubbs second generation catalyst produced the required carbocycles. [Copyright &y& Elsevier]

Abstract: A new strategy for the synthesis of 1,2-dideoxy iminosugar C-glycosides and indolizidines involving highly stereoselective [2,3]-Wittig rearrangement from Garner aldehyde has been developed. This rearrangement yielded an optically pure, highly functionalized key intermediate, which has been further utilized for the synthesis of 5-epi-ethylfagomine, 2-epi-5-deoxyadenophorine, and 5-hydroxymethyl indolizidine. [Copyright &y& Elsevier]

Abstract: A short and stereoselective synthesis of (−)-codonopsinol 5 and its C-2 epimer 6 were accomplished from commercially available starting material d-1,5-gluconolactone, using acid mediated amido cyclisation as the key step. The inhibitory activitiy of these compounds against glucosidase and galactosidase has been studied. [Copyright &y& Elsevier]

A common strategy for the synthesis of (−)-chloramphenicol and (+)-thiamphenicol is described. These antibiotics have been synthesized from commercially available 4-nitrobenzaldehyde and 4-(methylthio)benzaldehyde in three and four steps, respectively. [Copyright &y& Elsevier]

A versatile and efficient method for the preparation of (2S)-2-(hydroxymethyl)-N-Boc-2,3-dihydro-4-pyridone from l-(−)-phenylalanine 2 utilising the aromatic system as a masked β-keto aldehyde was developed. The key step in the sequence is an intramolecular cyclisation of 6 to give 2,3-dihydropyridin-4-ones. [Copyright &y& Elsevier]

Diversity oriented concise asymmetric syntheses of l -2,3- trans -3,4- cis -dihydroxyproline and (3 S ,5 S )-3,4,5-trihydroxypiperidine have been developed from ( R )-glycidol. The key step of the synthesis is Sharpless asymmetric dihydroxylation on enantiomerically pure TBDMS protected allylic alcohol 14 which generates the triol intermediate 15 in excellent de . The (2 R ,3 R ,4 S )-2,3-dihydroxypentanoate derivative 15 was subsequently converted to natural pyrrolidine azasugar 1 and non-natural piperidine azasugar 4 under cascade reaction conditions in good yields. [ABSTRACT FROM AUTHOR]

A concise synthesis of (2 R ,4 R )-4-hydroxyproline ( 1 ) and (2 S ,4 S )-4-hydroxyproline ( 2 ) has been developed in enantiomerically pure form from commercially available starting materials with excellent diastereoselectivity. The tightly bound chelation controlled transition state formed during the 5- exo - tet ring closure reaction is assumed to be the origin of high diastereoselectivity. [ABSTRACT FROM AUTHOR]